Jerusalem: Israel further tightened its grip on the West Bank Wednesday, arresting another 65 people, as Palestinian president Mahmud Abbas lashed out at those behind the kidnapping of three Israeli teenagers.

As the hunt for the youths entered its sixth day, there was no let-up in Israel`s drive to deal a crushing blow to the West Bank infrastructure of Hamas, which it has blamed for the kidnapping.

But as troops pressed their biggest arrest operation in years, imposing a tight lockdown on huge swathes of the West Bank, Abbas blasted those behind the teens` disappearance whom he said were trying to "destroy" the Palestinian people.

And he defended the coordination between the Palestinian security forces and their Israeli counterparts, sparking a furious denunciation by the Islamist Hamas movement.

"Those who kidnapped the three teenagers want to destroy us. We will hold them accountable," Abbas told a meeting of the Organisation of Islamic Cooperation in Saudi Arabia.

"It is in our interest to have security coordination with Israel, because that would help protect us," he said.

"We will never have another intifada -- that would destroy us," he added, referring to a new Palestinian uprising.

Hamas denounced his remarks as "harmful" to a fledgling reconciliation deal between it and the Palestinian leadership, which saw an interim government of technocrats replace rival administrations in the West Bank and Gaza earlier this month.

The exchange was the first public sign of a major dispute between the sides since the unity deal was signed in April, ending years of bitter and sometimes bloody rivalry.

Pundits have said Israel is seeking to use the massive military operation in the West Bank to bring about the collapse of the newly-formed unity government, established with the backing of its Islamist foe. "President Abbas`s statements on security coordination with Israel are unjustified, harmful to Palestinian reconciliation," Hamas spokesman Sami Abu Zuhri said.

The Palestinian leader`s remarks in Jeddah were also "a psychological blow to the thousands of Palestinian prisoners suffering a slow death in the occupation`s jails," he said, referring to around 5,000 detainees being held by Israel.

Although Israeli Prime Minister Benjamin Netanyahu has directly accused Hamas militants of being behind the kidnapping, the movement has dismissed his claims as "stupid."

Palestinian militants have long backed a policy of kidnapping Israelis for use as bargaining chips in securing the release of prisoners.

In October 2011, Israel began the staged release of 1,027 Palestinian prisoners in exchange for Gilad Shalit, an Israeli soldier held in Gaza by Hamas militants for more than five years.

So far, there has been no claim of responsibility for the teens` disappearance. Overnight, Israeli troops arrested another 65 Palestinians, among them 51 who had been released as part of the Shalit deal, in a move hailed by Netanyahu as sending "an important message."

Since the searches began early Friday, troops have arrested 240 Palestinians, searched more than 800 locations and raided 10 Hamas-run institutions, the army said.

But despite days of intensive military operations, there appeared to be no end in sight, with troops focusing on the southern city of Hebron and the surrounding area.

"They kicked the door in at 7:30am this morning and told us to leave... If our relatives didn`t live here, we`d have ended up on the street," said Umm Amr, a mother of four who lives in Taffuh village.

"I don`t think they`ll find the missing Israelis in the bathroom or the washing machine," snapped the woman sarcastically after soldiers also forced their way into her home.

"A lot of time will pass until the situation in the West Bank returns to what it was, if it ever does," an Israeli military official told Maariv newspaper.

Other officials said Operation Brother`s Keeper was likely to run into the Muslim holy month of Ramadan, which begins at the end of June.

"My feeling is their Ramadan is going to be disrupted," a senior military official told Haaretz newspaper, acknowledging that life in the West Bank was becoming increasingly difficult for the Palestinian population.

Military officials quoted by the paper said the normal easing of security measures during the fasting month were "liable to be suspended."